Robert Kingman Goodwin was born on May 23, 1905, in Des Moines, Iowa. He graduated from Drake University in 1928 and later attended law school at George Washington University in Washington, DC. After graduating from Drake, Goodwin moved to Redfield, Iowa, where he engaged in the brick and tile manufacturing business and farming. In 1939, he was vice president of the Dallas County Farm Bureau. Active in Republican Party politics, Goodwin was a delegate to the state conventions in 1936 and 1938. In 1940, he was elected to Congress, filling the vacancy caused by the death of Cassius C. Dowell. This term ended in January 1941, and Goodwin was not re-nominated. Commissioned as a lieutenant in the U.S. Naval Reserve in 1942, he served until 1945. Goodwin became the director of the Central National Bank and Trust Company in 1941 and remained in that position until 1965, when he returned to his manufacturing business. During the 1950s, he was a delegate to the Republican National Convention and was a member of the Republican National Committee. Robert K. Goodwin died on February 21, 1983, at the age of seventy-seven.

The papers of Robert K. Goodwin date from 1866 to 1983 and primarily concern Goodwin's political activities. There are correspondence files with letters from many Republican politicians, including H.R. Gross, Bourke B. Hickenlooper, and Herbert Hoover. Some of the political subject files include presidential inaugurations, Herbert Hoover Birthplace Foundation, Republican state conventions, and H.R. Gross. There are also copies of speeches given by Goodwin, biographical materials, and photographs.